一种新颖的三相四桥臂逆变器解耦控制的建模与仿真

三相四桥臂逆变器是针对三相不平衡或非线性负载的供电提出来的。该文提出了1种采用内环空间矢量电流调节器和外环同步坐标比例积分控制器相级联的三相四桥臂逆变器的控制方案，实现了对三相四桥臂逆变器的解耦控制。建立了三相四桥臂逆变器在αβγ空间的电路模型，分析了其在αβγ空间的三维电压矢量分布并由此提出了1种采用2个三电平滞环比较器和1个两电平滞环比较器相结合的内环电流调节方案。外环采用了同步坐标电压控制器，使用1个简单的比例调节器就可实现输出电压跟踪的零稳态误差，保证了良好的稳态性能。建立了整个系统在dqo坐标系下的控制模型，实现了对d,q,o3个分量的独立解耦控制。仿真结果验证了该控制方案的正确性与可行性。

MODELING AND SIMULATION OF A THREE-PHASE FOUR-LEG INVERTER BASED ON A NOVEL DECOUPLED CONTROL TECHNIQUE

Three-phase four-leg inverters are developed to power unbalanced/nonlinear three-phase loads. This paper presents a decoupled control scheme for three-phase four-leg inverter via an inner current regulator based on space vectors cascaded with an outer synchronous frame PI controller. Firstlya circuit model in abg coordinate system for three-phase four-leg inverter is established; then the three-dimensional space voltage vectors of four-leg inverter in dqo space are analyzed and an inner current regulation method implementedby two three-level hysteresis comparators and a two-level hysteresis comparator is presented accordingly. Outer voltage loop employs a synch-ronous frame PI controller. A simple proportional controller can be applied to three-phase output voltages to obtain zero steady-state error in theory, ensuring excellent steady-state perfor-mance. Control models of the whole system are established in dqo frame and a decoupled control of d, q, and o-components is realized. Simulation results verify the validity of the presented control scheme.